Bag closure and method of opening bags



April 1960 o. w. M DUFFIE 2,934,255

BAG CLOSURE AND METHOD OF OPENING BAGS Filed Aug. 19, 1955 f Zd- OOOOO OOQOQOO0000000000000OOOOOOOOQOOPOObOOOOggo- 26 I TO OPEN 5 'JLE FSZ /0 L2 f I Tiqz. 20 2,6

26/10000000009000OOOOOOOOOOOOOO ATTORNEY United States Patent BAG CLOSURE AND METHOD OF OPENING BAGS Orville W. MeDutfie, Teaneck, N.J., assignor to International Paper Company, New York, N.Y., a corporation of New York Application August 19, 1955, Serial No. 529,524

1 Claim. (Cl. 229-66) This invention relates to new and useful improvements in closures for multiwall paper bags and particularly seeks to provide a novel easily opened closure for such bags.

Accordingly it is an object of this invention to provide a multiwall bag which is closed by a transverse line of stitching with a sealing tape overlying the entire bag end and the stitching, and having a line of perforations superjacent the stitching which can be easily parted by pulling the end of the stitching thread across the bag and the line of perforations.

It is a further object to provide a method of opening bags of this character.

With these and other objects in view, the nature of which will become more apparent, the invention will be more fully understood by reference to the drawings, the accompanying detailed description and the appended claims.

In the drawings:

Fig. 1 is a perspective view of the upper end (after filling) of a multiwall bag embodying a closure constructed in accordance with this invention;

Fig. 2 is a view similar to Fig. 1 but with a portion of the tape broken away and showing the stitching thread being torn across the bag through the line of perforations;

Fig. 3 is a view similar to Fig. 1 but showing the bag after the stitching thread has been pulled out and the bag is opened.

Referring to the drawings in detail the invention as illustrated is embodied in a sewn open mouth rnultiwall bag generally designated having multiply front walls 12, multiply rear walls 14 and multiply side gussets 16 and 18.

Bags of this type are manufactured from a continuous length of multiply bag tubing which is severed to form individual bag blanks of proper configuration. The bottom of the bag as formed is square cut and is passed through a stitching and closure tape applying machine to close it. The bag is then filled and closed in a similar manner on the opposite top end. The emptying of the bag is a reverse procedure and the bottom of the bag as formed is turned uppermost and it is the bottom end that must be opened to discharge the contents of the bag.

In accordance with this invention the bottom (as formed) of the bag 10 (or the top of the bag after filling) is closed by the application of stitches along a line 20 extending across the bag near the edge thereof. The

2,934,255 Patented Apr. 26, 1960 stitches along the line 20 include a single thread continuous stitch 22 looped over a filler cord 24 and extending across the entire end of the bag in spaced parallel relation to the edge of the bag 10 to positions about /2 beyond either side of the'bag. As this line of stitching is applied a sealing tape 26 having a line of perforations 28 preferably on one side only is folded over the edge of the bag and adhesively secured thereto with the line of perforations overlying the stitchedv line 20. The sealing tape 26 is not secured to the bag front wall 12 in the area between the stitching and the edge of the bag, but it may be secured above and below the line of stitching or only below the line of stitching on the rear wall 14.

To open the bag after the bag has been filled with material and closed with the stitching and sealing tape 26 it is merely necessary to slightly tear the perforations 28 adjacent the side of the bag which would be the trailing edge of the bag as it leaves the sewing machine, and grab the free end of the thread 22 and pull it out across the bag through the perforations 28. The stitching 22 and the filler cord 24 will be pulled free of the bag but a portion of the sealing tape will remain adhesively secured to the rear wall 14 while the remaining portion will remain adhesively secured to the front wall 12.

A bag constructed in accordance with this invention can be opened without danger of having either the bag material or the sealing tape 28 tear off and contaminate the contents of the bag.

The invention provides a simple means for opening the bag without ripping the top edge ofli and without causing the sealing tape to be torn and severed from the bag. As shown in Fig. 1 lettering is applied to the top (after filling) of the bag 10 to indicate the position from which the perforations must be torn and the thread pulled out to open the bag.

It is of couse to be understood that various details of arrangements and proportions of parts may be modified within the scope of the appended claims.

I claim:

A closure for the open end of a multiwall paper bag comprising a line of stitching securing the opposing walls of the open end of the bag, said line of stitching terminating in free ends extending beyond said bag sides, and a sealing strip medially folded and adhesively secured to the exterior edge of one wall and covering the stitching and extending over the bag end and adhesively secured only below said line of stitching to the other wall, said strip having a line of perforations thereon extending across the full width of said sealing strip in alignment with said stitching and located on that face of the bag in which the sealing strip is adhesively secured thereto only below the line of stitching.

References Cited in the file of this patent UNITED STATES PATENTS 2,527,074 Port Oct. 24, 1950 FOREIGN PATENTS 287,251 Great Britain Mar. 22, 1928 481,327 Canada Feb. 26, 1952 

